package br.com.androidblog.database;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Environment;
import android.util.Log;

public class DataBaseConnector extends SQLiteOpenHelper {

	private static String DB_PATH = "/data/data/"
			+ "br.com.androidblog" + "/databases/";

	private static String DB_NAME = "androidblog.db";

	private SQLiteDatabase checkDB;

	public DataBaseConnector(Context context, String name,
			CursorFactory factory, int version) {
		super(context, name, factory, 1);
		this.myContext = context;
	}

	private static String DATABASE_NAME = "androidblog.db";

	private Context ctx;

	private SQLiteDatabase dbConnection;

	private SQLiteDatabase myDataBase;

	private final Context myContext;

	/**
	 * Constructor Takes and keeps a reference of the passed context in order to
	 * access to the application assets and resources.
	 * 
	 * @param context
	 */
	public DataBaseConnector(Context context) {

		super(context, DATABASE_NAME, null, 1);
		this.myContext = context;
	}

	/**
	 * Creates a empty database on the system and rewrites it with your own
	 * database.
	 * */
	public void createDataBase() throws IOException {

		boolean dbExist = checkDataBase();

		if (dbExist) {
			Log.i("agenda", "Banco de dados ja existe");
			// do nothing - database already exist
		} else {

			// By calling this method and empty database will be created into
			// the default system path
			// of your application so we are gonna be able to overwrite that
			// database with our database.
			this.getReadableDatabase();

			try {

				copyDataBase();

			} catch (IOException e) {
				throw new Error("Error copying database");
			}
		}

	}

	public SQLiteDatabase getConnection() {

		try {
			String myPath = DB_PATH + DB_NAME;
			if ((checkDB == null) || (checkDB != null &&  checkDB.isOpen() == false)) {
				checkDB = SQLiteDatabase.openDatabase(myPath, null,
						SQLiteDatabase.OPEN_READWRITE);
			}
		} catch (SQLiteException e) {
			
			throw new Error(e);
			// database does't exist yet.

		}
		return checkDB;

	}

	/**
	 * Check if the database already exist to avoid re-copying the file each
	 * time you open the application.
	 * 
	 * @return true if it exists, false if it doesn't
	 */
	private boolean checkDataBase() {
		Log.i("agenda", "Verificando se banco existe");

		try {
			String myPath = DB_PATH + DB_NAME;
			checkDB = SQLiteDatabase.openDatabase(myPath, null,
					SQLiteDatabase.OPEN_READWRITE);
		} catch (SQLiteException e) {
			// database does't exist yet.
		}

		if (checkDB != null) {
			checkDB.close();
		}
		return checkDB != null ? true : false;
	}

	/**
	 * Copies your database from your local assets-folder to the just created
	 * empty database in the system folder, from where it can be accessed and
	 * handled. This is done by transfering bytestream.
	 * */
	private void copyDataBase() throws IOException {
		Log.i("agenda", "copyDataBase");
		// Open your local db as the input stream
		InputStream myInput = myContext.getAssets().open(DB_NAME);

		// Path to the just created empty db
		String outFileName = DB_PATH + DB_NAME;

		// Open the empty db as the output stream
		OutputStream myOutput = new FileOutputStream(outFileName);

		// transfer bytes from the inputfile to the outputfile
		byte[] buffer = new byte[1024];
		int length;
		while ((length = myInput.read(buffer)) > 0) {
			myOutput.write(buffer, 0, length);
		}

		// Close the streams
		myOutput.flush();
		myOutput.close();
		myInput.close();
	}

	public void openDataBase() throws SQLException {

		// Open the database
		String myPath = DB_PATH + DB_NAME;
		myDataBase = SQLiteDatabase.openDatabase(myPath, null,
				SQLiteDatabase.OPEN_READONLY);
	}

	@Override
	public synchronized void close() {
		if (checkDB != null) {
			checkDB.close();
		}
		if (myDataBase != null)
			myDataBase.close();
		super.close();

	}

	@Override
	public void onCreate(SQLiteDatabase db) {

	}

	@Override
	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

	}

	/**
	 * 
	 * @param ctx
	 * @param tableName
	 * @param returnElements
	 * @param orderBy
	 * @return
	 */
	public Cursor search(Context ctx, String tableName,
			String[] returnElements, String orderBy) {
		return search(ctx, tableName, returnElements, null, orderBy);
	}

	/**
	 * 
	 * @param ctx
	 * @param tableName
	 * @param returnElements
	 * @param having
	 * @param orderBy
	 * @return
	 */
	public Cursor search(Context ctx, String tableName,
			String[] returnElements, String having, String orderBy) {
		return getConnection().query(tableName, returnElements, null, null,
				null, having, orderBy);
	}

	/**
	 * 
	 * @param sql
	 * @param argumentos
	 * @return
	 */
	public Cursor searchCustomSQL(String sql, String argumentos) {
		if (argumentos != null) {
			return getConnection().rawQuery(sql, new String[] { argumentos });
		} else {
			return getConnection().rawQuery(sql, new String[] {});
		}
	}

	/**
	 * 
	 * @param ctx
	 * @param tableName
	 * @param addElements
	 */
	public void addElements(Context ctx, String tableName,
			HashMap<String, String> addElements) {
		Iterator i = addElements.entrySet().iterator();
		ContentValues cv = new ContentValues();
		while (i.hasNext()) {
			Map.Entry me = (Map.Entry) i.next();
			cv.put(me.getKey().toString(), me.getValue().toString());
		}
		getConnection().insert(tableName, null, cv);
	}

	public void updateElements(String tableName,
			HashMap<String, String> elementsUpdate, String whereClause,
			String whereArgs) {
		Iterator i = elementsUpdate.entrySet().iterator();
		ContentValues cv = new ContentValues();
		while (i.hasNext()) {
			Map.Entry me = (Map.Entry) i.next();
			cv.put(me.getKey().toString(), me.getValue().toString());
		}

		getConnection().update(tableName, cv, whereClause,
				new String[] { whereArgs });
	}

	public void deleteElements(String tableName, String whereClause,
			String whereArgs) {
		getConnection().delete(tableName, whereClause,
				new String[] { whereArgs });
		
	}

}
